The present invention relates to an apparatus for controlling a friction clutch, which is capable of carrying out the engaging operation of a friction clutch with high efficiency.
There have been proposed various friction clutch controlling apparatuses which have an actuator connected to the friction clutch and are capable of engaging/disengaging the friction clutch in response to an electric signal provided from outside. This type of clutch controlling apparatus is confronted with the problem of how to carry out the engaging operation of the friction clutch smoothly and this problem has been solved in the conventional apparatus by gradually decreasing the slip rate from the start of the engagement of the clutch. In more detail, the conventional apparatus is adapted to carry out the engaging of the friction clutch in accordance with programmed control for driving the actuator in such a way that the slip rate of the clutch gradually changes from 1 (completely disengaged state) to zero (completely engaged state) at a predetermined changing rate when clutch engagement has been commanded.
Therefore, in the conventional device, the actuator is driven in such manner as to vary the slip rate of the clutch from 1 to zero at a predetermined change rate even when the command for engaging the clutch is given to engage the clutch at a time when the slip rate of the clutch has already become a value less than 1. Consequently, it is decided that the clutch has been operated too far in the direction of engagement at the start of the engagement of the clutch, so that the operation for engaging the clutch is maintained in a waiting condition for a time equal to that normally required for the clutch to reach the degree of engagement at that time. Consequently, an efficient engaging operation of the clutch cannot be carried out because this waiting condition of the engaging operation wastes time which could have been used for control operation and prevents the time taken for engaging the clutch from being shortened.